Joshua 4:10-12

MLV(i) 10 For the priests who bore the ark stood in the midst of the Jordan until everything was finished that Jehovah commanded Joshua to speak to the people, according to all that Moses commanded Joshua. And the people hastened and passed over. 11 And it happened, when all the people were clean passed over, that the ark of Jehovah passed over and the priests, in the presence of the people.
12 And the sons of Reuben and the sons of Gad and the half-tribe of Manasseh, passed over armed before the sons of Israel, as Moses spoke to them.